お年玉
おとしだま New Year's gift (usu. money given to a child by relatives and visitors)
Why it means this
年 (the year) + 玉 (a jewel, a round precious thing) — the New Year's gift of money to children, once a round rice cake offered to the year-god and shared out.
Breakdown
Each character links to its full entry — origin story, stroke order, and readings.